Free fall container



Jan. 14, 1964 D. F. HASTINGS FREE'FALL CONTAINER INVENTOR Dwig'hzFfiasting's 2 Sheets-Sheet 1 Filed Oct. 24, 1962 Hz/M v ATTORNEY Jan.14, 1964 D. F. HASTINGS FREE FALL CONTAINER 2 Sheets-Sheet 2 Filed 001;.24, 1962 INVENTOR l'fiastimg' Dwight Haw M United States Patent3,117,666 FREE FA'LL CONTAINER Dwight F. Hastings, 14} Princeton Road,Wellesley, Mass. Filed Oct. 24, 1%2, Ser. No. 232,913 14 Claims. (Cl.150-1) (Granted under Title 35, US. Code (1952), see. 266) The inventiondescribed herein, if patented, may be manufactured and used by or forthe Government for governmental purposes without the payment to me ofany royalty thereon.

The present invention relates to containers and method of packaging anddelivering materials. More particularly the invention relates tocontainers for flowable materials which will remain intact after theshock or impact of a free fall and methods for packaging and deliveringsuch materials by free fall techniques.

Air drop delivery of supplies is employed by the military to supplyunits that have become isolated from the main body or that have rapidlyoutdistanced existing supply lines. Additionally, in many areas of theglobe, the terrain is such that it becomes more expedient to supply byair than by the more conventional modes of transport. It is essential inair drop delivery that the supplies be (1) accurately placed or droppedwithin a relatively small area and (2) that the supplies be deliveredintact and undamaged. Low altitude free fall drops satisfy therequirement for pin point accuracy and possess the added advantage ofbeing diflicult to detect. Parachute delivery, on the other hand, is notpractical at low altitudes and tends to disperse the supplies over awide area under the influence of the prevailing wind currents.

To survive a free fall, i.e., a fall not employing means to slow therate of descent, a container must be designed or engineered to withstandthe abrupt and extreme force of impact. The prior art has developedcomplex, sophis ticated and somewhat cumbersome containers that are ableto survive a free fall impact, however, such containers aside from beingunwieldly are also expensive and do not satisfy the need for alightweight, inexpensive and expendable free fall container.

It is an object of the present invention to provide a novel containerfor flowable materials capable of resisting failure resulting from theimpact of a free fall. *It is also among the objects of the presentinvention to provide an inexpensive, lightweight, easy to manufactureand easy to handle container for flowable materials that is adapted toresist impact forces.

More particularly, it is an object to provide a container 0 having novelmeans to absorb or dissipate the shock of impact.

Another object is to provide a method of packaging and delivering aquantity of flowable materials by free fall from an elevated point to alower surface.

Various other objects and advantages will appear from the followingdetailed description of an embodiment of the present invention taken inconjunction with the accompanying drawings wherein:

FIGURE 1 is a perspective view of the empty container.

FIGURE 2 is an elevational view of the container of the presentinvention partially filled with flowable material and shown in free fallattitude.

FIGURE 3 is an elevational view of the container of FIGURE 2 at impactand showing the progressive failure of the shock cushioning elements.

FIGURE 4 is a transverse section of the container of FIGURE 1.

FIGURE 5 is an elevational view of the container at rest after a freefall impact.

Referring now more particularly to FIGURES 1 and 4 there is shown anempty, collapsed, flexible container or 3,li'"i,6fl Patented Jan. 14,

enclosure designated generally by numeral 19, which is circular inoutline. The container is readily constructed by placing one circularsheet 11 of flexible material, e.g., Mylar (a polyester film) having athickness of approximately 6 mils and approximately 37 inches indiameter, upon a second similar sheet 12 and sealing together theperipheral edge portions 13 and 14.

A suitable closure device 15 communicating with the interior of thecontainer is located on the top central portion thereof. As shown indetail in FIGURE 4 the cylindrical closure body 16 has a circular flangebase 17 which extends radially outwardly of the upright body portion andis positioned superadjacent the outer surface of upper sheet 11. Areinforcing washer 18 is placed over the flange base 17 and the washer,flange base and upper sheet are sealed together. The outer wall of theclosure body has external threads which mate with the internal threadsof a suitable cap 19 which completes the closure.

In the filling operation, the container is grasped near the open closureand a flowable material, e.g., water, is poured into the containerpartially filling the container. A container of the size described canadequately accommodate 5 gallons of fluid. While it is preferred thatthe container have not more than half its maximum volume occupied by theflowable contents it is possible by the use of either low densitycontents or stronger container materials to load the container to morethan half its maximum volume and still have it successfully Withstandthe impact of a free fall. The partially filled container supported fromthe closure assumes more or less a pearshaped outline with the fluidoccupying the base of the container and an empty tail portion 22extending above the fluid. The loose flexible material forming the tailis gathered together in a more or less straight line extending upwardlyfrom the base thereby restricting or decreasing the volume of thecontainer.

From a point above the level 2d of the liquid an adhesively coated tape21, approximately /2 inch wide, e.g., a cellophane pressure sensitiveadhesive tape, is tightly wound in an upward spiral about the tail. Thetape serves initially to restrain or hold together the gathered folds ofthe tail. The cap is tightly closed and the partially filled containerhas an oppearance substantially as is shown in FIGURE 2.

The tape winding serves as a shock cushioning means and acts to reducethe pressures that are rapidly built up in the container at the momentof impact. The container is now ready for free fall delivery.

At the desired height, the loaded container of the present invention isreleased and in free fall the base portion containing the fluid assumesor maintains a forward position with respect to the tail portion in theflight trajectory. As the base portion of the container strikes theground the energy of the free fall of the liquid is converted intolaterally acting component forces which exert pressure on the walls ofthe container. The pressure, which otherwise would have been suificientto rupture the container with a resulting loss of the contents, stressesand breaks the tape at intervals along its upward spiral path. With eachstepwise break of the tape shown in FIGURE 3 the effective volume of thecontainer increases stepwise permitting the liquid to flatten out andthe forces tending to rupture the container are rapidly diminished ordissipated. The tape will continue to break progressively as long as theforces exerted on the walls of the container are greater than thetensile strength of the tape. Each rupture or break of the tape absorbsor overcomes part of the pressure exerted by the liquid. It is importantthat for each loaded container, the tail length and ability of the shockabsorbing means to absorb the energy of the fall be 3 suflicient toinsure that the forces being transmitted do not travel all the way tothe closure.

FIGURE 2 represents an embodiment of a container of the presentinvention as it would appear in a free fall. In FIGURE 3, the containeris shown as it strikes the surface. It may be observed that the liquidcontents and the walls of the container tend to flatten and that thetape binding, in response to pressure, breaks at rather close intervalsto permit the tail to open increasing the volume of the inclosure toaccommodate the flattening liquid. The container is finally shown atrest in FIGURE 5 after surviving a free fall.

While in the above described embodiment of this invention the shockabsorbing means is applied subsequent to the filling of the container,it is also contemplated that the shock absorbing means may be applied tothe container prior to the filling operation. If it is desired topractice the invention in this manner, it is only necessary to insurethat the restraining means only partially constricts the gathered tailportion such as by the use of a rigid tube or pipe inserted thereinduring the application of the restraining means so that the laterfilling of the container will not be impeded.

The tail of the container serves not only to carry the shock cushioningmeans but also functions as a handle for carrying the container and as astabilizer to orient the container in flight so that it will land on itsbase.

While the shock absorbing means has been particularly described as anadhesive cellophane tape material other tape materials, e.g.,thermoplastic solid tapes, fabric tapes, having a suitable adhesivebase, may be employed. The preferred shock absorbing materials are tapeshaving an adhesive thereon but other non-adhesive materials such astape, cord, or string may be employed if there are suitable retainingmeans located on the tail of the container such as loops through whichthe materials may be attached. The loops may constitute the shockabsorbing means if their breaking point is below that of the containerand the tape or cord.

It is important for successful operation that the shock absorbing meansbe the weak link of the container, i.e., that the latter have aresistance to rupture greater than the former. In place of thecontinuous spiral wound shock absorbing means one may wrap or bind anumber of spaced apart individual bands or segments about the tail.

The container may be formed of solid sheets of thermoplastic materials,e.g., polyethylene, polypropylene, polyester, etc., which may be singleor multiple plies. Rather than solid sheets, fabric sheets may beemployed in some instances. Where rugged or jagged terrain is to beencountered an inexpensive reinforcing sole of similar or punctureresisting material may be attached to the base of the container. While apreferred embodiment of the container has been described in detailabove, other shapes and types of construction of the container arepossible.

The term flowable materials as used herein refers not only to liquidsbut also to finely divided solid materials.

It will be understood that various changes in the details, materials,steps and arrangements of parts, which have been herein described andillustrated in order to explain the nature of the invention, may be madeby those skilled in the art within the principle and scope of theinvention as expressed in the appended claims.

I claim:

1. A container for fiowable materials capable of withstanding the impactof a free fall comprising a flexible enclosure partially filled withflowable material, the remaining empty portion of said enclosuregathered forming a tail thereby reducing the volume of the enclosure,means circumferentially restraining the gathered tail portion along atleast a portion of its length, said means having a tensile strength lessthan the tensile strength of the enclosure whereby the forces of impactending to flatten and rupture the enclosure are spent in stressing andrupturing i the restraining means sequentially along the length of thetail.

2. A container for flowable materials capable of withstanding the impactof a free fall comprising a flexible enclosure f led to not more thanabout half s maximum volume with flowable material, the unfilled portionof the enclosure is gathered in a line forming a tail and reducing thevolume of the enclosure, means encircling and restraining the gatheredta stepwise along a portion of its length, said means havgrg a tensilestrength less than the tensile strength of the enclosure whereby theforces of impact tending to flatten and rupture the enclosure are spentstressing and rupturing the restraining means.

3. A container as in claim 2 wherein said means is a tape having anadhesive coating.

4. A container for flowable materials capable of withstanding the impactof a free fall formed of a flexible material impervious to said flowablematerials, said container partially filled with said flowable materials,the empty portion of the container extended forming a tail above thefilled portion of the container, means encircling and partiallyconstricting and binding the tail from a point above and adiacent to thefilled portion to the opposite end of said tail, said means having atensile strength less than the tensile strength of the container wherebythe forces of impact tending to flatten and rupture the container arespent in sequentially stressing and rupturing said means along the tail.

5. A container according to claim 4 wherein said means comprises tapehaving a coating that will adhere to the container.

6. A container for flowable materials capable of withstanding the impactof a free fall formed of a flexible material impervious to said flowablematerials, said container filled to less than about half its maximumvolume with said flowable materials, the remaining unfilled portion ofthe container is extended forming a tail above the filled portion, tapehaving a coating that adheres to the container circumferentially bindingand partially constricting the tall from a point above the filledportion to the opposite end of the tail, said tape having a tensilestrength less than the tensile strength of the container so that theforces of impact tending to flatten and rupture the conainer are spentin sequentially stressing and rupturing the tape binding along thelength of the tail.

7. A container according to claim 6 wherein said container is formed oftwo circular sheets of flexible material sealed together along theirperipheral edges and having a closure located therein.

8. A container according to claim 6 wherein said tape is spirally woundabout said tail.

9. A container for flowable materials capable of withstanding the impactof a free fall comprising a flexible enclosure, a portion of saidenclosure gathered forming a tail thereby reducing the volume of saidenclosure, means circumferentially restraining the gathered tail alongat least a portion of its length, said means having a tensile strengthless than the tensile strength of the enclosure whereby the forces ofimpact tending to flatten and rupture the enclosure are spent instressing and rupturing the restraining means sequentially along thelength of the tail.

10. A container for flowable materials capable of withstanding theimpact of a free fall comprising a flexible enclosure, about half ofsaid enclosure gathered forming a tail thereby reducing the volume ofsaid enclosure, means circumferentially restraining the gathered tailalong at least a portion of its length, said means having a tensilestrength less than the tensile strength of the enclosure whereby theforces of impact tending to flatten and rupture the enclosure are spentin stressing and rupturing the restraining means sequentially along thelength of the tail.

11. A container for fiowable materials capable of withstanding theimpact of a free fall comprising a spherical flexible enclosureimpervious to said flowable materials,

s,117,eoe

about half of said enclosure gathered forming a tail thereby reducingthe volume of said enclosure, means circumferentially restraining thegathered tail along at least a portion of its length, said means havinga tensile strength less than the tensile strength of the enclosurewhereby the forces of impact tending to flatten and rupture theenclosure are spent in stressing and rupturing the restraining meanssequentially aiong the length of the tail, and a cleseable openingthrough which said fiowable materials be introduced or emptied locatedon the Wall of said enclosure.

12. A container according to claim 11 wherein said means is anadhesively coated tape spirally wound about said tail.

13. A method of packaging a quantity of fiowable material for free falldelivery comprising partially titling a flexible enclosure with saidfiowable material, gathering the unfilled portion of said enclosure toform a tail thereby reducing the volume of the enclosure, applyingrestraining means cireumierentially along at ieast a portion of thelength of the tail, said means having a tensile strength less than thetensile strength of the enclosure whereby the forces on impact tendingto flatten and rupture the enclosure are spent in stressing andrupturing the restraining means sequentially along the length of thetail.

ii. A method of delivering a quantity of flowaole material from a heightto the surface below by free fall which comprises placing said flowahlematerial in a container formed or" a flexible enclosure, a portion ofsaid enclosure gathered forming a tail thereby reducing the volumethereof, means circumferentiaily restraining the gathered taii along atleast a portion of its length, said means having a tensile strength lessthan the tensile strength of the enclosure, releasing the loadedcontainer from the desired height and permitting it to fall and strikethe surface below whereupon the forces of the impact which wouldotherwise flatten and rupture the container are spent in stressing andrupturing the restraining means sequentially along the length of thetail.

No references cited.

1. A CONTAINER FOR FLOWABLE MATERIALS CAPABLE OF WITHSTANDING THE IMPACTOF A FREE FALL COMPRISING A FLEXIBLE ENCLOSURE PARTIALLY FILLED WITHFLOWABLE MATERIAL, THE REMAINING EMPTY PORTION OF SAID ENCLOSUREGATHERED FORMING A TAIL THEREBY REDUCING THE VOLUME OF THE ENCLOSURE,MEANS CIRCUMFERENTIALLY RESTRAINING THE GATHERED TAIL PORTION ALONG ATLEAST A PORTION OF ITS LENGTH, SAID MEANS HAVING A